1. Field of the Invention
The present invention relates to a semiconductor integrated circuit, and more particularly, to a semiconductor integrated circuit suitable for power-supply noise reduction.
2. Description of Related Art
In a semiconductor integrated circuit, there has been a problem that data transmission between transmitter-receivers is not accurately executed when power-supply noise occurs on signal lines used for the data transmission between the transmitter-receivers. To reduce the power-supply noise, reducing the impedance of the signal lines has been required.
Therefore, a countermeasure, for example, ODT (On Die Termination) technique has been provided to reduce the power-supply noise on signal lines used for data reception of transmitter-receivers (JEDEC STANDARD, DDR2 SDRAM SPECIFICATION JESD79-2E (Revision of JESD79-2D), April 2008, JEDEC SOLID STATE TECHNOLOGY ASSOCIATION). Specially, a bidirectional signal line for bidirectionally transmitting data between the transmitter-receivers is equipped with a termination circuit which switches on an ODT function when receiving the data and switches off the ODT function when not receiving the data in each transmitter-receiver.